Theses and Dissertationshttp://hdl.handle.net/11714/103
Tue, 26 Sep 2017 21:50:15 GMT2017-09-26T21:50:15ZA Realistic Simulation for Swarm UAVs and Performance Metrics for Operator User Interfaceshttp://hdl.handle.net/11714/2095
A Realistic Simulation for Swarm UAVs and Performance Metrics for Operator User Interfaces
Ahmed Siddiqui, Kazi Tanvir
Robots have been utilized to support disaster mitigation missions through exploration of areas that are either unreachable or hazardous for human rescuers [1]. The great potential for robotics in disaster mitigation has been recognized by the research community and during the last decade, a lot of research has been focused on developing robotic systems for this purpose. In this thesis, we present a description of the usage and classification of UAVs and performance metrics that affect controlling of UAVs. We also present new contributions to the UAV simulator developed by ECSL and RRL: the integration of flight dynamics of Hummingbird quadcopter, and distance optimization using a Genetic algorithm.
Sun, 01 Jan 2017 00:00:00 GMThttp://hdl.handle.net/11714/20952017-01-01T00:00:00ZMechanisms of Interactions between Aerosol Physics and Atmospheric Dynamicshttp://hdl.handle.net/11714/2094
Mechanisms of Interactions between Aerosol Physics and Atmospheric Dynamics
Hosseinpour, Farnaz
This study gained novel insights into mechanistic interactions of dust and smoke particles with large-scale climate dynamics. This study revealed that the variability Saharan dust radiative properties is significantly linked to high-frequency atmospheric wave activity across the tropical Atlantic storm tracks, while the variability of smoke particles from the South African biomass burning is attributed by low-frequency oscillations of baroclinic instability of the region. We proposed that the impacts of Saharan Air Layer (SAL) on large-scale climate dynamics mainly occur through coupling of dust radiative forcing with eddy energetics of the African easterly jet-African easterly waves (AEJ-AEWs) systems. This study quantified the thermal/mechanical impacts of oceanic SAL on activity of the AEWs and the regional feedback of eddies onto the mean-circulations from a climatological point of view. We found that both upstream and downstream developments of eddy energy are affected by oceanic SAL radiative forcing. It is suggested that dust radiative forcing has the capability to affect the transient changes in baroclinic instability of the jet-wave system through eddy available potential energy, and contribute in exchange of kinetic energy between the AEWs and AEJ through baroclinic and barotropic conversions. This study discussed that Saharan dust radiative properties have both constructive and destructive effects on behaviors of the AEWs, which depend on structure of the waves at different time-scale: the eddy kinetic energy (EKE) of the 2—6-day ultrahigh-frequency waves are amplified in average 1-day after enhancing of dust radiative forcing, while the EKE of the 6—11-day intermediate-frequency waves weakens during dust storm events. In addition, over the western African monsoon (WAM) region and the entrance of the tropical Atlantic storm track, the 2—6-day filtered AEWs become more barotropic during oceanic SAL outbreaks. The anomalous changes in meridional and quadruple momentum fluxes of 2—6-day filtered AEWs, associated with enhanced dust in the oceanic SAL, tend to an easterly feedback onto the southern edge of the mean-AEJ. However, at the middle- to exit region of the southern storm track, the anomalous convergent momentum fluxes of 2—6-day AEWs, associated with dust outbreak, tends to increase the regional baroclinic instability through the 3 main local energy packets, which may initiate a higher chance of hurricane activity. Applying ensemble of large NASA satellite observations data sets, such as MODIS, SeaWiFS and TRMM as well as GOCART aerosol model and MERRA reanalysis indicates that the suggested results are consistent regardless of the selected data sets. Overall, we proposed that the regional radiative properties of aerosols and thermal/mechanical activity of wave-jet systems are dynamically coupled and it is not suggested to consider either as a response to one another.
Sun, 01 Jan 2017 00:00:00 GMThttp://hdl.handle.net/11714/20942017-01-01T00:00:00ZAqueous Organometallic Catalysis: Nitrile Hydration Catalyzed by Ruthenium(II) 1,3,5-triaza-7-phosphaadamantane (PTA) Derived Complexeshttp://hdl.handle.net/11714/2092
Aqueous Organometallic Catalysis: Nitrile Hydration Catalyzed by Ruthenium(II) 1,3,5-triaza-7-phosphaadamantane (PTA) Derived Complexes
Ounkham, Whalmany Linglee
This dissertation investigates the synthesis and characterization of ruthenium complexes containing water-soluble 1,3,5-triaza-7-phosphaadamantane (PTA) and PTA derived ligands for the application of aqueous phase nitrile hydration. A series of PTA and PTA derivatives were characterized via solid-state NMR (SSNMR) and compared to their corresponding solution NMR spectra. Highly water-soluble β-phosphino alcohols (PTA-CR1R2OH) were prepared by reacting lithiated PTA with pyridiniecarboxaldehyde (e.g. 2-, 3-, or 4-pyridinecarboxaldehyde). A series of ruthenium arene β-phosphino alcohol (PTA-CR1R2OH) complexes were prepared by reacting highly water-soluble 2-, 3-, or 4- pyridyl PTA derivatives with the corresponding Ru arene (arene = toluene, p-cymene, or benzene) dimer [(arene)RuCl2]2. Ruthenium arene complexes containing PTA-CH-(2py)OH (20) resulted in monodentate κ1-P and bidentate κ2-P,N coordination modes. Complexes containing PTA-CH-(3py)OH (21) displayed predominately κ1-P coordination mode with a minor impurity (possibly a bridging species). The PTA-CH-(4py)OH (22) yielded a mixture of κ1-P and bridging coordination modes. All compounds were characterized by 1H, 13C, and 31P NMR spectroscopy and ESI-MS. The air-stable and water-soluble ruthenium complexes are active in catalytic hydration of nitriles to amides in water under air at 100°C. Our group previously reported RuCl2PTA4 as a highly active catalyst for aqueous phase nitrile hydration with tolerance for a wide substrate scope (e.g. ether, hydroxyl, nitro, bromo, pyridyl, and alkyl). The in situ generated catalyst (RuCl33H2O + 6 equivalents PTA) was found to be comparably active for nitrile hydration in water. In situ catalyzed nitrile hydration was evaluated in pH 6.8 buffer solution at 100°C under air and demonstrated higher activity than what was observed when conducted in water. Similar substrate tolerance, easy product separation (e.g. decantation), and recyclability was observed. Mechanistic studies (e.g. inhibition experiments, salt effects, and cyanide poisoning experiments) were conducted for this system. The final portion of this dissertation focuses on chemical education and active/inquiry-based learning (IBL) projects developed during an NSF GK-12 E-Fellowship for an Advanced Placement (AP) chemistry class. A combination of materials (e.g. brain teasers and class discussions) was used for curriculum development with inquiry-based experiments as a primary tool. The development of skills (e.g. critical thinking, problem-solving, and communication skills) through the exposure of IBL was empirically assessed.
Sun, 01 Jan 2017 00:00:00 GMThttp://hdl.handle.net/11714/20922017-01-01T00:00:00ZThe Design and Synthesis of Monomers for use in Two-Dimensional Polymerizationshttp://hdl.handle.net/11714/2091
The Design and Synthesis of Monomers for use in Two-Dimensional Polymerizations
Patterson, Dustin Day
The focus of this dissertation is the design and synthesis of monomers for use in the synthesis of two dimensional polymers (2DPs). 2DPs can be described as laterally connected repeat units which cover a plane with no gaps or overlaps. Monomers used for the synthesis of 2DPs must be designed with at least three reactive functional groups; this permits polymerization into a 2D sheet of repeat units. A total of seven different monomer designs were synthetically sought out. Three of the seven monomers, 1-H, 1-MeO, and 1-F are previously reported and their synthesis was improved upon. Synthesis of three novel monomers, 1-FOH, 1-FPOH, and 1-PZn was attempted with the completion of two of the three targets 1-FOH, 1-PZn and a known derivative, 1-P. The above monomers were designed with anthraceno functionalities intended to undergo [4+4] cycloadditions during solid state and air-water interface polymerizations. The monomers intended for polymerization at the air-water interface (1-FOH, 1-FPOH and 1-PZn) were designed with synthetic handles for attachment of a hydrophilic substituent. A pyridine-DEG ligand was synthesized to ligate 1-PZn at the air-water interface. Growth of single crystals of 1-P and 1-H:C70 co-crystals were grown and irradiated at 365 nm, 400 nm, and 465 nm at 100 K-250 K. However, no polymerization occurred because a proper packing motif allowing a topochemical 2D polymerization was not achieved.Monomer, 1-pyz, was synthesized using a novel route which takes advantage of Suzuki coupling chemistry. 1-pyz possesses three pyrazole functionalities intended to undergo coordination with a metal center during polymerization. Monomer 1-pyz relies on reversible coordinative bonding in solution to form a metal coordinated lamellar crystal that can be exfoliated into single 2DP sheets. The highly insoluble monomer was reacted with various Ag, Au, and Mn salts under high temperature and superheated high pressure conditions towards polymerization. A single crystal containing metal coordinated layers of 1-pyz has yet to be realized.
Sun, 01 Jan 2017 00:00:00 GMThttp://hdl.handle.net/11714/20912017-01-01T00:00:00Z